This invention generally relates to the art of electrical connectors and, particularly, to an improved means for securing or fixing an electrical connector to a printed circuit board.
A typical electrical connector includes some form of dielectric housing which mounts a plurality of conductive terminals. The electrical connector may be mounted on a printed circuit board, and the terminals may have tail portions for surface connection, as by soldering, to circuit traces on the board or for insertion into holes in the board for connection, as by soldering, to circuit traces on the board and/or in the holes. Problems continue to be encountered with circuit board mounted electrical connectors caused by damaging forces placed on solder joints between the terminal solder tail and the respective circuit trace on the board.
In order to prevent solder joint damage, various means have been used to mechanically secure or fix the connector housing to the printed circuit board. Such means include fasteners, solderable fitting nails fixed to the dielectric housing, a plated surface on the dielectric housing or a metal housing which, itself, is soldered to a pad on the circuit board. Unfortunately, with the ever-increasing miniaturization of electrical connectors, fasteners are difficult to apply. Fasteners do not work well with smaller connectors, and they require inventory storage and shipment of separate components. Solderable fitting nails typically are inserted into slots in the sides of the connector housing and do not provide support at the middle of the housing between the sides. Plating the connector housing with solderable material can be effective, but such plating processes are quite expensive in comparison to the overall cost of the connector and is not even cost effective for most applications. A metal connector housing may be effectively soldered to pads on the printed circuit board, but metal housings are unduly heavy in comparison to plastic housings and it is difficult to solder beneath the housing which effectively acts as a thermal heat sink. The present invention is directed to solving these problems by providing a board mounted electrical connector with an improved means for securing or fixing the connector to a printed circuit board.
An object, therefore, of the invention is to provide a new and improved board mounted electrical connector.
In the exemplary embodiment of the invention, the connector includes a dielectric housing having a bottom face for mounting on a printed circuit board. An elongated solder bar of solderable material is secured to the bottom face of the housing for mechanically fixing the housing to an appropriate solder pad on the board. The elongated solder bar has opposite ends and is provided with air vent openings spaced between the opposite ends to facilitate air flow during a soldering process.
Preferably, the dielectric housing includes cut-out areas behind the solder bar in registry with the air vent openings. This improves the air flow in the area of the vent openings.
According to one aspect of the invention, the housing has an elongated rib. The elongated solder bar is U-shaped in cross-section and embraces the rib. The U-shaped solder bar defines a pair of side wall portions joined by a base wall portion. The vent openings are located at least in the base wall portion. In the exemplary embodiment, the vent openings extend into the side wall portions of the U-shaped solder bar. The rib has cut-out areas in registry with the vent openings.
According to another aspect of the invention, the dielectric housing is molded of plastic material and is overmolded over portions of the solder bar to secure the bar to the housing. Preferably, the solder bar includes a plurality of holes into which the molded material of the housing projects.
According to a further aspect of the invention, the dielectric housing includes an elongated air vent channel adjacent to and extending along substantially the length of the elongated solder bar. This elongated air vent channel preferably is wider at a central area thereof than at opposite end areas thereof.
Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings.